Eye Witness Testimony

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Eye Witness Testimony

• Dr. Jenny Wilson

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Recall the crime you just witnessed

• Write down what happened

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Recall of the incident

• Interviewer Group 1
• A) There have been other reports of a gang
  working the area - Was the assailant working with
  an accomplice/ accomplices?

• Interviewer Group 3
• B) Describe the incident from other witnesses
  point of view what do you think the two boys
  saw of the assailant?

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Recall of the incident

• Eye witness Groups 2 4
• Do you think the assailant was working alone? Or
  not?
• Why?
• Lets look back at interviewer questions how
  could these influence responses?

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Eyewitness testimony Definition

• A witness is someone who has first-hand knowledge
  about a crime or dramatic event through their
  senses (in this case seeing) and can certify to
  its happening.
• A witness who has seen the event at first-hand
  is known as an eye-witness.
• Witnesses are often called before a court of law
  to testify in trials.

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Importance of EWT to legal Process

• EWT is considered crucial evidence in terms of
  both
• The identification arrest of a suspect
• The likelihood of juries convicting a defendant
• Also civil cases e.g. car accident

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How does memory work?

• Memory is not like a video-recorder.
• We do not make an exact copy of what we
  experience.
• We reconstruct our memory, retelling it so that
  it makes sense.
• Often so that it forms a plausible (not always
  reliable) story

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How good is our memory for familiar things?
Image shown in lesson!
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And the real.
Were you right? Or did you expect it to be.
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Face Recognition EWT
Whats wrong with the picture (shown in lesson!)
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If you're going to rob a bank, wear a wig!

• Unless we are paying close attention to facial
  features, hair plays a big part in forming an
  image of individuals
• The upper part of the face seems to be more
  important for recognition than the lower part.
• The hair seems to be the most important factor,
  followed by the eyes, then the nose, and then to
  a lesser extent, the mouth and chin.

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Face recognition
Who are we?

• These faces are top and bottom composites of two
  famous people.
• The upper part of the face is usually more
  helpful in recognition than the lower part.

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Face recognition
chairman Mao
Richard Nixon
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How good is our memory for faces?

• http//faculty.washington.edu/chudler/java/facemem
  2.html

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Classic errors in EWT Ronald Cotton Case Study

• What Jennifer saw
• Ronald Cotton was convicted of the rape of two
  women.
• 11 years later thanks to DNA evidence he was
  exonerated
• http//www.pbs.org/wgbh/pages/frontline/shows/dna/
  cotton/summary.html.

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Prosecution evidence

• A photo identification was made by one of the
  victims.
• A police lineup identification was made by one of
  the victims.
• This witness was composed, determined, and sure.
• Circumstantial evidence A flashlight in Cotton's
  home resembled the one used by the assailant.
  Rubber from Cotton's tennis shoe was consistent
  with rubber found at one of the crime scenes.
• In court the victim testified her rapist was
  Cotton. (Not real rapist Bobby Poole)

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Cottons conviction

• Largely on the grounds of the witness evidence,
  Cotton was convicted.
• A miscarriage of justice occurred.
• Why?

If you had been a juror in that case what do you
think you would have done?
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Face Identification

• How good are we at constructing a face?
• Take a look at the photfit.
• Now build it up
• http//www.pbs.org/wgbh/pages/frontline/shows/dna/
  photos/pick/index.html

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Matching the photofit to the person
B
A
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Process of Eyewitness testimony
Acquisition what you saw

• Memory is a process that can largely be divided
  into three main stages
• Acquisition (encoding)
• Storage (retention)
• Retrieval (recall)
• Mistakes can occur in any of these stages

Storage how long hold it in memory
Retrieval what you recall
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Process of Eyewitness testimony

• Within these stages other Factors exert an
  influence over eye witness accounts.
• These are
• Event (stimulus) factors e.g. time of day/ length
  of time of crime.
• Witness (subject) Factors e.g. age, or race of
  witness.

As we discuss them consider which stage they
apply to whether they are event or subject
factors
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Factors affecting EWT

• AGE of witness
• Children and the elderly tend to be less accurate
  than other age groups.
• Older adults have problem with source monitoring

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Factors affecting EWT

• Weapon focus effect
• People tend to keep their eye on weapons because
  of their danger and novelty
• This distracts their attention from the robbers

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Factors affecting EWT

• Cross-racial identification
• People are more accurate at recognising members
  of own race
• This can be mediated by experience

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Facial Distinctiveness

• Faces rated highly attractive OR highly
  unattractive are better recognised than other
  faces.

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Factors affecting EWT

• Perceived Seriousness of Crime
• people tend to be less accurate in identification
  tests if the the crime is thought to be less
  serious
• BUT highly violent crimes also poor recognition
  (weapon focus or stress)

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Why dont really serious crimes brand our
memory?

• Well they do good memory for emotional
  experience
• STRESS interferes with encoding of detail
• BUT conversely, low level of arousal also means
  details arent encoded.

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Factors affecting EWT
How might this affect appeals?

• Retention period
• Our memories for conversation, events etc. tend
  to fade with time.
• BUT memory for faces a little more resistant,
• Nonetheless does decline over long time intervals
  
• Decline in correct identification with time delay

Recall what the cashier looked like last time you
went to the post office?
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Factors affecting EWT

• Viewing Opportunity
• The longer witnesses look and the more attention
  they are able to pay, the more accurate their
  identifications
• However, witnesses are just as likely to think
  they can make an identification if they have
  witnessed an event under poor viewing conditions.

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Factors affecting EWT

• Post Event Information
• Our memory is not entirely objective we subject
  to biases in our recall.
• Information (from suggestive questioning or
  media) can become incorporated into our memory
  for the event

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Improving EWT

• Hypnosis
• No hard evidence that peoples memories improve
  when they are hypnotized,
• BUT evidence that people under hypnosis are
  susceptible to suggestion, coming to believe that
  they saw things that they did not.

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Improving EWT

• The Cognitive Interview Fisher Geiselman
  (1988)
• We have seen leading and suggestive questioning
  can sometimes affect EWT
• In the CI a trained interviewer tries to improve
  eyewitnesses memories by focusing their
  attention on the details and context of the
  event.
• This allows more cues for recall

More on this in CI lecture!!